from invoices
filter invoice_date >= @1970-01-16
derive {
  transaction_fees = 0.8,
  income = total - transaction_fees
}
filter income > 1
group customer_id (
  aggregate {
    average total,
    sum_income = sum income,
    ct = count total,
  }
)
sort {-sum_income}
take 10
join c=customers (==customer_id)
derive name = f"{c.last_name}, {c.first_name}"
select {
  c.customer_id, name, sum_income
}
derive db_version = s"version()"
